/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.chukwa.datacollection.collector.servlet;
import java.io.DataInputStream;
import java.io.IOException;
import java.io.PrintStream;
import java.util.*;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.chukwa.Chunk;
import org.apache.hadoop.chukwa.ChunkImpl;
import org.apache.hadoop.chukwa.datacollection.writer.*;
import org.apache.log4j.Logger;
public class ServletCollector extends HttpServlet {
static final boolean FANCY_DIAGNOSTICS = false;
static org.apache.hadoop.chukwa.datacollection.writer.ChukwaWriter writer = null;
private static final long serialVersionUID = 6286162898591407111L;
Logger log = Logger.getRootLogger();// .getLogger(ServletCollector.class);
public static void setWriter(
org.apache.hadoop.chukwa.datacollection.writer.ChukwaWriter w)
throws WriterException {
writer = w;
}
static long statTime = 0L;
static int numberHTTPConnection = 0;
static int numberchunks = 0;
static long lifetimechunks = 0;
Configuration conf;
public ServletCollector(Configuration c) {
conf = c;
}
public void init(ServletConfig servletConf) throws ServletException {
log.info("initing servletCollector");
if (servletConf == null) {
log.fatal("no servlet config");
return;
}
Timer statTimer = new Timer();
statTimer.schedule(new TimerTask() {
public void run() {
log.info("stats:ServletCollector,numberHTTPConnection:"
+ numberHTTPConnection + ",numberchunks:" + numberchunks);
statTime = System.currentTimeMillis();
numberHTTPConnection = 0;
numberchunks = 0;
}
}, (1000), (60 * 1000));
if (writer != null) {
log
.info("writer set up statically, no need for Collector.init() to do it");
return;
}
try {
String writerClassName = conf.get("chukwaCollector.writerClass",
SeqFileWriter.class.getCanonicalName());
Class<?> writerClass = Class.forName(writerClassName);
if (writerClass != null
&& ChukwaWriter.class.isAssignableFrom(writerClass))
writer = (ChukwaWriter) writerClass.newInstance();
} catch (Exception e) {
log
.warn(
"failed to use user-chosen writer class, defaulting to SeqFileWriter",
e);
}
// We default to here if the pipeline construction failed or didn't happen.
try {
if (writer == null)
writer = new SeqFileWriter();// default to SeqFileWriter
writer.init(conf);
} catch (WriterException e) {
throw new ServletException("Problem init-ing servlet", e);
}
}
protected void accept(HttpServletRequest req, HttpServletResponse resp)
throws ServletException {
numberHTTPConnection++;
ServletDiagnostics diagnosticPage = new ServletDiagnostics();
final long currentTime = System.currentTimeMillis();
try {
log.debug("new post from " + req.getRemoteHost() + " at " + currentTime);
java.io.InputStream in = req.getInputStream();
ServletOutputStream l_out = resp.getOutputStream();
final DataInputStream di = new DataInputStream(in);
final int numEvents = di.readInt();
// log.info("saw " + numEvents+ " in request");
if (FANCY_DIAGNOSTICS) {
diagnosticPage.sawPost(req.getRemoteHost(), numEvents, currentTime);
}
List<Chunk> events = new LinkedList<Chunk>();
ChunkImpl logEvent = null;
StringBuilder sb = new StringBuilder();
for (int i = 0; i < numEvents; i++) {
// TODO: pass new data to all registered stream handler
// methods for this chunk's stream
// TODO: should really have some dynamic assignment of events to writers
logEvent = ChunkImpl.read(di);
sb.append("ok:");
sb.append(logEvent.getData().length);
sb.append(" bytes ending at offset ");
sb.append(logEvent.getSeqID() - 1).append("\n");
events.add(logEvent);
if (FANCY_DIAGNOSTICS) {
diagnosticPage.sawChunk(logEvent, i);
}
}
// write new data to data sync file
if (writer != null) {
writer.add(events);
numberchunks += events.size();
lifetimechunks += events.size();
// this is where we ACK this connection
l_out.print(sb.toString());
} else {
l_out.println("can't write: no writer");
}
if (FANCY_DIAGNOSTICS) {
diagnosticPage.doneWithPost();
}
resp.setStatus(200);
} catch (Throwable e) {
log.warn("Exception talking to " + req.getRemoteHost() + " at "
+ currentTime, e);
throw new ServletException(e);
}
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
accept(req, resp);
}
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
PrintStream out = new PrintStream(resp.getOutputStream());
resp.setStatus(200);
String pingAtt = req.getParameter("ping");
if (pingAtt != null) {
out.println("Date:" + ServletCollector.statTime);
out.println("Now:" + System.currentTimeMillis());
out.println("numberHTTPConnection:"
+ ServletCollector.numberHTTPConnection);
out.println("numberchunks:" + ServletCollector.numberchunks);
out.println("lifetimechunks:" + ServletCollector.lifetimechunks);
} else {
out.println("<html><body><h2>Chukwa servlet running</h2>");
if (FANCY_DIAGNOSTICS)
ServletDiagnostics.printPage(out);
out.println("</body></html>");
}
}
@Override
public String getServletInfo() {
return "Chukwa Servlet Collector";
}
@Override
public void destroy() {
try {
writer.close();
} catch (WriterException e) {
log.warn("Exception during close", e);
e.printStackTrace();
}
super.destroy();
}
}